BERKELEY — Berkeley could become the first city in the country to mandate climate change warning labels on gas pump hoses. The signs would inform drivers that the state has determined CO2 emissions contribute to global warming.

“It’s not going to be earth-shattering consequences, but I think it’s a clever way to get more people to think,” said City Councilman Kriss Worthington, who sponsored the bill. “It’s not going to immediately cease purchase at the gas pump. That’s not our goal. The point of sale is a great place to have people stop and think about the impact.”

Berkeley’s Community Environmental Advisory Commission voted 6-1 in approval of recommending the stickers on gas pumps to the City Council. A council vote on the proposed ordinance is expected in the fall.

The city’s Energy Commission has requested a report on the issue and is scheduled to vote on it in July.

The idea is modeled on the warnings on cigarette packaging and pushed by the grass-roots environmental group 350 Bay Area. The goal of the stickers is to influence human behavior at the point of sale, said Jamie Brooks, manager of 350 Bay Area’s Beyond the Pump campaign.

“The labels are a hopeful message that we all are capable of changing the outcome of the global warming problem,” he said. “The label identifies you as part of the problem. It’s a gentle reminder that says, ‘Hey, you can do something with what you drive. We need to cooperate to deal with this problem.'”

He said that the labels would create a needed sense of urgency and that he hopes they serve as a model for other cities to adopt the idea. The group, 350 Bay Area, is working with San Francisco Supervisor John Avalos on developing a similar policy. A Toronto-based organization called Our Horizon is working on the same issue.

The Western States Petroleum Association opposes the labels. In a letter to the advisory commission, President Catherine H. Reheis-Boyd wrote that “far less restrictive means exist to disseminate this information to the general public without imposing onerous restrictions on businesses and forcing unwanted speech in violation of the First Amendment.”

The labels are not “warnings” but instead “forced reproductions of the State’s and the City’s policy opinions,” she wrote. “They do not convey ‘fact.'”

The city attorney and additional outside counsel have vetted the legality of the proposed ordinance, Worthington said.

“Research has indicated that we are not pre-empted by state and federal law,” he said. “The language will be carefully chosen words that have been adopted by California and consistent with the overwhelming majority of the scientific community.”

All 20 gas stations in Berkeley have been notified about the label, and none has expressed disapproval, he said.

Reheis-Boyd also touched upon Berkeley’s “rich tradition in the exercise of the First Amendment right to freedom of speech.”

Brook said that science supports the campaign.

“This isn’t just lefty kooky Berkeley speaking,” he said. “Berkeley is doing something rational. This is in line with the city’s and the state’s climate plans.”

If the City Council approves the warning labels, drivers could see them next spring, Worthington said.